Electric switch



Nov. 15, 1927.

F. HENK l ELECTRIC SWVITCH Filed oct. 29, 1925 WITNESS v nvr-rouwenl Patented Nov. 15, 1927.

UNITED STATES PATENT OFFICE.

FREDERICK HENKE, OF PHILADELPHA, PENNSYLVANIA, ASSGNGR T FOX AUTO- MOTIVE PRCDUCTS CORPORATION, A CORPORATION OF DELAWARE.

i ELECTRIC SVITCII.

Application filed October 29, 1925,

My invention relates to manually operated y electric switches in which, after the handle y closing or operating member has been moved up to a certain point, and before the movable contact of the switch has moved away from the stationary contact point with which it may be in engagement, an automatic mechanism rapidly throws the `arm to another position which may be a position in which the movable contact point is out of engagement with said stationary Contact point, or it may be into engagement with the second stationary contact point7 whereby the making and breaking of the circuit is substantially instantaneous. Such electric switches are employed for a variety ot usesr but my improved snap switch is particularly adapted tor the ignition circuits of automobiles and especially those wherein the ignition circuit may be supplied at will with current trom one of `two sources, namely, from a storage battery or (2) from a generator or magneto. y

One of the objects ot' my Vinvention is to provide a construction wherein the snap ot the movable contact arm from the battery Contact point to the magneto contact point or vice versa is so rapid that ai supply of current to the ignition system is practically uninterrupted or is interri'ipted for so short a time that the production of sparlrsat the spark plugs is not interrupted and the motor cannot be stalled in changing the circuit from one source of supply to the other.

A further object of my invention is to pro-- vide a snap switch `which is comparatively small in size and is certain in its action and in which the parts are so protected and enclosed that one may not close the switch at the contact points when the switch is open withoutturning the handle; that is to say, one in which it is practically impossible to insert or drop a wire into the casing thereby the circuit through the contact points. i

itifturther object of my invention is to providea manually operable switch for the ignition circuit of an automobile whichis adapted to be placed or located on the dashboard oi a car ata point or position where it is convenient for the driver to manipulate the switch and is so constructed that it is practically impossible to accidentally throw the switch.

A further object ot' my invention is to Serial No. 65,845.

provide a snap switch of the character above described which must be grasped by the hand ot' the operator and turned in order to throw the switch. f

.A further object ot my invention is to provide a snap switch ot the character above described which cannot be thrown by accidentally hitting the handle.

Further objects ot' my invention will appear in the specification and claims below.

Referring to the drawings forming a part oi the speciiication and in which the same reference characters are employed through* out the various views to indicate the same parts,

Fig. 1 is a front elevational improved switch.

Fig. 2 is a rear view of the switch mecha-` nism, the dashboard being broken away to permit a view of the inside of the casing of the switch; in the position showin the circuit may be considered as closed through the magneto or generator of an ignition system.

Fig. 3 is another rear view of the switch with the parts thrown to close the circuit through the battery.

Fig. il is a substantially vertical sectional view on the line lof F 2.

Fig. 5 is a more or less diagrammatic view of the parts at the time when the automatic switch throwing` mechanism is about to op'- crate.

Fig. G is a'view similar to Fig. l of a slightly modified construction wherein the switch is adapted to coact with a` steering wheel loclr7 the switch being arranged to hold the ignition circuit closed either through the battery or the magneto so long view of my vas the steering wheel or other locking part of an automobile is unlocked and in which, after the motor has once been started, the circuit cannot be broken until after the lock is locked.

A switch similar to that illust-rated in Fig. 6, and combined with a steering wheel loclr, forms the subject-matter of my copeuding application, Serial Number 711,848, tiled Mfay 6, 1924:.

Upon the front ot the dashboard l is mounted the switch casing 2. Preferably, the casing Q is heldto the dashboard by screws 3--8 passing through suitable holes 4 4: through the casing and provided on the rear side of' the dashboard with nuts 5-5. A sheet7 6, of insulating material is preferably llt) interposed between the back of the casing 2 and the front of the dashboard' 1, particularly when the dashboard is of metal or is of wood covered with a facing 7 of metal,

through which the ignition circuit might be ing material, such as balrelite, and is pro-` vided with a circularrecess or depression 8 in the rear face thereof, forming therein the chamber 8 in which is housed the con tact points and switch mechanism. Embedded in the material of the casing 2 and preferably in the bottom of the depression and near the lower edge of said casing, are two insulated stationary contact pieces' or points 9 and 10, preferably alike and extending substantially through the vertical wall of the casina; with the inner faces respectively flush with the bottom of the chamber 8. On their outer ends said stationary contact points 9 and 10 are preferably provided with binding screws 11 and 12 respectively for the attachment theretoof the wire 13 which may lead to the magneto and the wire 14 which may lead to the storage battery. Preferably the outer surfaces of the front face and of the bottom edge of the casing 2 are provided with grooved channels or" depressions 15, 16, substantially semicircular in cross-section at thebottoms thereof and in which the insulated wires 13 and 14 are respectively seated or fitted so that the top or outer surface of the said wires or conductors are justbelow the surrounding plane surfaces of the casing.

At the center of the chamber pr depression 8 is a metal stud 17 extending fromthe bottom of the depression to the outside of the casingf and this stud 17 is provided on its front end with a binding screw 18 for the attachment thereto of a conductor or wire 19 running' to the induction coils `(not shown) of the ignition system. This wire 19 is also preferably fitted in a groove or channel 2O extending' parallel to the channels 15 and 16. The inner end of the stud 17 projects above the bottom surfaces of the depression 8 and forms a `iournal or shaft on which is pivotally mounted the switch arm 21 and the cam member 22, the said arm and cam being retained on the stud 17 between the head of the screw 23 threaded intothe inner end of the stud 17 and a shoulder 211 provided on the stud. A lic-ht washer 25 may be interposed between the switch arm 21 and the shoulder 241. Both the switch arm and the cam member are free to turn on the stud 17.' They are capable of a slight in- Leeasco dependent movement relative to each other` about said stud 17 as a pivot but such 1no tion is limited by a pin 26 projecting from the rear surface of the arm 21 and entering a hole or opening 27 through the-cam member 22, said opening 27 being of a little larger diameter than the diameter of the pin 26.

The upper side of the cam member 22 is provided with a few gear teeth 28 which are adaptedto mesh with enacting gear teeth 29 in the perimeter of a disc 30 rigidly mounted on the inner end of a shaft 31 mounted torotate in a bushingl or bearing 32 fixedly molded into and passing through the front wall of a switch casing 2. The outer end of the shaft. 3l is provided with a. knob or handle 33, secured thereto by a transverse pin 311 passing through the shaft and through the huh of the knob 33. The knob or handle 33 may be provided with an index or pointer 35 by the position of which with respect to suitable indications 36, 37, such as MAG and BAT the operator may throw the switch to obtain his power for the ignition system .from either source of electricity.

At opposite ends of the gear teeth 28 on the cam member 22 are stop projections or shoulders 38 and 39 respectively adapted to abut against the cylindrical surface otv the disc 3() to limit the throw of the disc and cam.

The outer end of the switch arm 21 is preferably provided with a. metallic contact point 40 having a smooth undersurface adapted t0 freely slide over the smooth surfaces 9 and 10 of the stationary contact points 9 and 1() respectively and over the smooth inner fiat bottom surface of the chamber S between said stationary contact points `9 and 10. Because the` insulating material of which the casing: 2 may be composed may be somewhat softer than metal and may therefore in time become abradcd by the sliding' of the Contact 40 thercover, I prefer to embed in the casing substantially midway between the Contact points 9 and 10 a metallic pin or stud 41, the end of which is flush with the bottom of thedepression or chamber 8. The contact point 21 will thus slide over and wear the metallic contact points 9 and 10 and the pin 41, and the material between the contact points 9 and 10 willnot be worn away. It will be evident that the wearing away of the insulatingr material between the .contact points 9 and 10 would in time produce shoulders at the adjacent edges of the stationary contactstl and 10. and such shoulders might interfere with the smooth movement of the contact point 40 thereovcr.

The arm 21 is preferably a resilient arm arranged to press the contact point 4110 firmly against the metallic surfaces aboi'e referred to, and therefore, to hold this contact point l0 securely at the end oit the arm 21, it is merely necessary to provide the rear side of the contact el() with a small stud 4t2 litt-ing into ay cylindrical hole 43 at the end ot the arm 21. The resiliency ot' the arni 21 pressing against the contact point 40 will prevent its separation troni the arm 21 during the ordinary manipulation of the switch. Should the contact point Llllbec-oine worn and need should be found to replace the same, it is a comparatively simple inatter to spring the arm 21 away trom the bottoni ot the depression 8,\separate the contact point Ll() therefrom and replace it with a new contact point.

The cani member 22 is also provided with a cani project-ion 'ist which is somewhat heart-shaped or triangular and the high point ot this cani is preferably a sharp edge extending transverse to the tace oft the cam and parallel to the axis thereo't. On both sidesl of this sharp edge 45, the cani projection l0 preferably curves downwardly away troni the sharp edge Zl5 toward the stud or shaft 17.

Cooperating with the said projection all on the cani 22 is a` cam follower il@ which iis operative, at the proper time, to snap the switch arm 2l from one Contact point to the other point 10 and vice versa and this member mayconsist of a` lever pivoted at one end on apivot screw or stud Lili". rllhe tree end of said pivoted member lo is preterably provided with ay stud or pin fltl to which one end ot' a spira-l spring t9 is attached, the other end oit said spring being similarly connected to a stud or pia 50 rigidly mounted in the bottom ot the recess or chamber 8. rlhe rfollower meii'iber L16 on the side adjacent the cani member 22 is preterably also provided with a. projection 51 terminating in al relatively sharp edge and the sides of the projection il on each side oit the edge 52 are preferably curved downwardly and away from the said edge 52. The edgel also extends transverse to the pivoted member 2G parallel to the axis ot' the cani member 22 and parallel to the sharp edge The sharp edges l5 and 52 on the cani ineinber 22 and "follower member 46 are preferably so disposed with respect to each other than when the apex ot the projection le ot the cam is midway between the stationary contact points -9 and 10 or i more broadly when the cam member 22 has been. moved tor one-hall ot its complete throw, the edge l5 on the cam will be in alinenient with the sharp edge 52 onthe member 4to. lt is, o't course, impossible tor these two sharp edges to remain in this position. The tension oft the spring 49 is such that the instant. thesharp edge l5 on the cani passes over the sharp edge 52 on the member 46, t-he spring will ininiediately advance the cani independently of the liandle or lniob 33 and snap the arm 21 to the other stationary contact point 10. "lliiscrit-V ical position ol" the cani and switch throw` ing member a6 is illustra-ted in Fig. 5.

@ver the Ctront ot the. switch casing 2l preferably provide a` plate or cover which lits against the flat tace of the switch casing l and against. the under edge of it over the such as libe'r or ot metal and lined with inf siilating` material. In the preferred form of my invention, thel pla-tc is otl metal and between it and the casing 2 I preferably insert a. thin sheet ot insulating inaterial so that it by any chance the binding screws 1l and 12 work loose and outwardly so tar as to maire contact with the cover, the

sheet ot' insulating material will prevent any sho-rtcirciiiting ot the ignition system` as would occur were the pla-te or cover 53 to be inade ol conducting material and without such. an inner lining 55 ot insulating inatcrial. t tor the saine purpose that the sheet (3 ol insulating material is placed under the switch casing and between it and the dashboard 1, tor il the tace ol the dashboard were a metal sheet, and the heads of the screws 28 and et? became loose and worked out into contact. with such electrically con-r diictivc surface, shortcircuiting` ot' the ignition systeii'i would take place. v

Having thus described the preferred form ot' iny invention, it will be plain that with the parts constructed and arranged as shown in Fig. 1, the ignition circuit ot an autoniobilewould be closed through the inagneto wire 13, the stationary contact point 9, the movable contact or switch arm 21, the metallic stud 17, the binding screws 18 and the wire 1S). ln the position shown in Fig. 2 the ignition circuit would be closed through the battery wire 1st, stationary contactpoint 10, the switch arm 21, the stud 17, bach lo wire 19.

Tothrow the magneto out from the igni-y tion circuit and thro-w the battery into the. ignition circuit7 the operator would turn the lrnob or handle 33 to bring the index 31 trom the position shown in Fig. 3 toward the indication Biii T. lllhen the operator has so turned the knob 33 and brought the parts connected thereto up to the position shown in Fig. 5, the movable contact point- 40 will still be on the stationary Contact point 9, the

cut-ting cam 22 willhave completed one-halt ot its complete throw, and the sharp edge l5 thereof will be substantially coincident with the sharp edge 52 on the member 16. The instant the sharp edge l5 passes the sharp edge 52 on the member 16,

the spiral springl 19 will draw the pro` trical engagement with the stationar7 con- `plugs of the tactI point 10. This motion or throw ot the arm 21 is rapid and substantially iiistanta neous. The space between the contact points 9 and 10 is but a liairs breadth greater than the diameter ot the contact Ll0 on the end ot the arm 21 so that while the contact ll() may not be in engagement with both stationary7 Contact points at the same instand-that is to say,--ma v not close the ignition circui through the battery and through the maejne to simultaneously, the time that the Contact 40 is out oi electrical engagement with both stationary contacts is intinitesin'ial and the ignition circuit isl'or practical purposes unbroken. An instantaneous break and make of the circuit will not interrupt the regular continuous production of sparks at the spark ignition system.

The loose connection between the movable contact or switch arm 21 and the cam 22 is a loose intermeshing` or inter-engaging connection and is of such a nature as to cause the switch arm to lag: behind the cam as it is being dragged along` by the cam in either direction and the space between the pin 2G on the arm and the hole 2 in the cam i. so proportioned that the contact point el() on the arm 20 cannot bel manually moved out oit engagement with a stationary contact point until the sharp edge Ll5 on the cam has passed over the sharp edge 52 on the follower or switch throwing member 'lt.

It is to be understood if the hole were in the arm 21 and the pin on the cam the operation would be substantially the same.

In Fia'. 6 is shown a niiodiiied construction of my `improved switch member particularly` adapted and arranged for cooperation with the holt 5G ot a steeringl wheel loclr (not shown). ln this construction the switch casing is placed under the bolt 5G and the inden tinger or pointer 35 of the construction shown in Fig. ll is extended upwardly to form an arm or handle 3f intothe path ot motion ot which the bolt 56 extends when the steering wheel is unlocked. This type oit steeringr wheel lock and an ignition switch cooperating therewith is :fully disclosed in when thc steering wheel is locked and the bolt 55 is out ot the path ol movement ot the arm 35', then the contact arm 21 may move by the cam follower `iurther to the right ot the magneto stationary` contact point tl to a position shown in Fig. (j where it is out of contact therewith and the ignition circuit to the battery and to the magneto is broken and no current is supplied to the i ignition circuit.

. 'lo eil'ect its operation, it is merelj,r necessary to provide the cam member 22 and the disc 3G with one or more teeth 28 and 29 respectively and to position the stop lugs 38 and 3( so as to permit ot' a slightly greater movement oit the arm 21 in a clockwise di rection (when looked at 'from the rear ot the switch` as in Fig. 10) so that the cam 22 may be moved by the follower e6 to swing the contact Ll0 out et electrical engagement with the magneto contact point 9.

The operation olf the two mechanisms is exact-ly alike except when the bolt :5G is in a locked position and extends into the path oi the arm it acts as an abutment to pre vent the further movement oi the arm 21 in an anticloclrwise direction and the stud projection 39 prevents the movement ot the arm 21 `in a clockwise direction further than the position shown in Fig. G when the cam is locked and the bolt 56 is out oit the path ol the arm 35..

While the embodinient illustrated on the drawings has been described with considerable particnlarity, it is to be expressly understood that the invention is not to be rcstricted thereto, as the saine is capable ol resewingy a variety7 ot mechanical expressions, some oli which will readilj,r suggest themselves to these skilled in the art, while cer tain parts thereof are capable et use without other parts thereof. lelerence is therefore to he had to the claims heretoappended for the detinitions of the limits oi' this invention,

Having thus described my invention, what l claim and desire to protect by Letters Patent oi the United States, is:

1. ln a switch mechanism the combination oi a recipro able cam, the high portion ot which presents an acute angle, a cam `follower having a projection presenting; an acute angle. yielding means continually pressing said projection against said cam, a movable contact member, a loose connection between said member and said cam whereby said member is dragged by said cam and whereby said member lags slightly behind said cam in its motion in either direction,

`a reciprocable operatingmeniber manually tion terminating in a relatively sharp edge extending transverse to the plane of movement of said cam, a cam followerA` yielding means continually pressing said follow-er against said cam, a movable contact member. a loose connection between said member and said cam, a. manually reciproeable cani-operating member operable to more said cam fromweither endof its path of movement to a point substantially midway of its path of movement and a looseldrivingi' connection between said Cani-operatingv member and said cam. y

3. In a switch mechanism, the combination with two stationary Contact points.` of a reciprocable cam, the high portion o!" which terminates in a sharp .edge extendingl transverse to the plane of movement of said cam. a cam follower, yielding means pressing' ysaid follower against said cam, said cam and follower being positioned rso that when said cam has been moved substantially one-half of its Complete reciprocatory movement in one direction the engagement between said cam and said follower will be on the side of said edge and the pressure of said follower on said cam will rapidly advance said cam for the balance of its movement in said direction, a movable contact arm member, a looseconnection between said member and said cam whereby said member lags slightly behind said cam when moved thereby` and a manually reciprocable Cam-operatingl member operable to move said cam up to said point Where said cam follower begins to advance said cam, there being a substantial backlash between said cam-operating member and said cam.

4. In a switch mechanism, the combination of alreciprocable cam pivoted to rotate on a fixed axis and providing a projection at the high point of which is a relatively sharp edge extendingT parallel to the axis of said cam, a 4cam follower' pivoted on a ixed axis parallel to the axis of said cam and having a projection also terminating in a sharp edge extending parallel to the sharp edge of said cam, yielding means continually holding said cam follower pressed against said cam, a movable contact arm pivoted on the axis of taid cam, a loose connection between said arm and said cam, a manually reciprocable cam-operating member, a loose connection between said eana-operatingV member and said cam, and a stationary Contact point at one end of the path of movement of said arm, said -ani and follower being so positioned with respect to each other and to said contact point thatwhen the edge of said cam is coincident with the edge on said projection of said follower, said arm is still in engagement with .said Contact point.

5. ln a switch mechanism the combination with two stationary contact points, of a reciprooable cam, the high point of which terminates in a. sharp edge extending transverse to the plane of the movement of said cam, a cam follower having` a. projection engaping said cam and also terminating in a sharp edge extending parallel to the Said edge on said cam, said cam and follower being` positioned so that when the cam has been mov-ed to a position substantially midway between the limits of its reciprocatorf movement, -said edges are coincident, yieldineY means pressing' said follower against said cam, a movable contact member. a loose connection between said contact member and said cam whereby said member is dragged by said cam ,trom one to the other of said stat-ionary contact points, a manually reciprocable ca11i-operating` member operable to move said cam up to said position where said Iedges are coincident, and a loose Aconnection between said cam-operating member and said cam. l

6. lin a switch. operating` mechanism, the

vcombination with two stationary contact points, of cam pivoted to reciprocate on a fixed axis and having a high portion terminating in a sharp edge extendingl parallel to said axis, a cam follower' also mounted on a fixed axis parallel to the axis of said cam and having a. projection terminating in a sharp edge and parallel to the sharp edge of said cam, yielding means continually pressing` the projection on said cam follower against said cam, a movable Contact arm pivoted on the axis of said cam and loosely connected to said cam whereby said arm is moved by said cam but lags a little behind it :in its movement in either direction, a manually reciprocable cam-operating member also pivoted to rotate on an axis parallel to the axis of said cam, said cam and said cam-operating member beirng` provided with-intermeshing teeth having` a substantial backlash between them, said edges on said cam and follower being so positioned with respect to' each other that the edge on said cam will pass over the sharp edge on said cam follower before said arm leaves the stationary contact point with which it is in contact.

lli

7. In a switch mechanism, the combination ot a reciprocatory cam providing a projection terminating in a relatively sharp edge lextending transverse to the plane of movement of said cam, a cam follower, yielding means continually pressing said follower against said cam, a movable contact member a loose intermeshing connection between said member and said cam, al manually reciprocable cam-operating member operable to move said cam fromreither end of its path oi movement to a point substantially midway or" its path oi movement and a loose driving connection between said cam-oper ating member and said cam.

8. In a switch mechanism, the combination of a reciprocatory cam providing a projection terminating in a relatively sharp edge extending ytransverse to the plane of movement o't' said cam, a cam follower, yielding means continually pressing said i'ollower against said cam', a movable contact member, a loose connection between said member and said cam, a manually reciprocable cam-operating member operable to move said cam from either end of its path of movement to a point substantially midway ot' its path oi' movement and loosely intermeshing gearing between said eam-operating member and said cam.

` 9. In a switch mechanism, the combination` of a recillarocatory cam providing a projection terminating in a relatively sharp edge extending transverse to the plane or' movement of said cam, a cam follower, yielding means continually pressing said follower against said cam, a movable contact member, a loose intermeshing connection between said member and said cam, a ma`nnally reciprocable earn-operating member operable to move said cam from either end olf its path ot' movement to a point substantially midway of its path `of movement and loosely intermeshing gearing between said cam-operating member and said cam.

l0. In a switch mechanism, the `combination with two stationary contact points, of a reciprocable cam, the high portion of which terminates in a sharp edge, a cam follower, yielding means pressing said follower against said cam, said cam and follower be ing positioned so thatwhen said canallas been moved substantially one-half of its complete movement in one direction, the pressure of said follower on said cam will advance said cam for the balance of its' movement in said direction, a movable contact arm, movable back and forth from one oi said stationary Contact points to the otl1er,a loose connection between said movable contact arm and said cam, whereby said mm'ablc contact arm lags slightly behind said cam when moved by said cam, a manually reciprocable cam operating member, operable to move said cam up to a point where said cam follower begins to advance saidcam, and a loose connection between said cam and said cam operating member, the distance between said stationary contact points being slightly greater than the width ot' that portion of the movable contact arm in cngagen'ient with said stationary contact points. s

In testimony whereof, I have hereunto set my hand this 26th day of October, 1925.

FREDERICK HENKE. 

